NEW YORK (AP) — Last Thanksgiving Day, Kimberly Mudge Via’s mother, sister and nieces left in the middle of their meals to head for the mall.

Now, Via says she’ll never host Thanksgiving dinner for her relatives again.

“They barely finished,” says the 28-year-old who lives in Boone, N.C. “They thanked me and left their plates on the counter.”

That scene could become more common in homes across the country. Black Friday shopping, the annual rite of passage on the day after Thanksgiving, continues to creep further into the holiday as more stores open their doors a day early.

It’s a break with tradition. Black Friday, which typically is the year’s biggest shopping day, for a decade has been considered the official start to the busy holiday buying season. Stores open in the wee hours of the morning with special deals called doorbusters and stay open late into the evening. Meanwhile, Thanksgiving and Christmas remained the only two days a year that stores were closed.

Now Thanksgiving is slowly becoming just another shopping day. Over the past few years, major retailers, including Target and Toys R Us, slowly have pushed opening times into Thanksgiving night to one-up each other and compete for holiday dollars. Some initially resisted, saying that they wanted their employees to be able to spend time with their families.

This year, Macy’s, Wal-Mart and Kohl’s are among at least a dozen major retailers that are opening on Thanksgiving. Several are opening for the first time, and others, including Gap, are opening earlier on the holiday than they did last year.

Roger Beahm, professor of marketing at the Wake Forest University School of Business in Winston-Salem, N.C., expects that it’s just a matter of time — he estimates five years — before most chains open all day on Thanksgiving. As for Christmas, he says that day is still sacred among shoppers.

“The floodgates have opened,” Beahm says. “People will turn Thanksgiving Day shopping into a tradition as they historically have on the day after Thanksgiving … And stores don’t want to be left behind.”

Indeed, retailers say they’re just doing what shoppers want. And they know that opening earlier gives them a chance to be the first to grab shoppers’ dollars. That’s an important opportunity for chains, which can make up to 40 percent of their annual revenue during the last two months of the year.

But so far, it’s unclear whether opening on Thanksgiving boosts retailers’ top line or simply pushes forward sales from Friday. Last year, it was the latter: Sales on Thanksgiving were $810 million last year, an increase of 55 percent from the previous year as more stores opened on the holiday, according to Chicago research firm ShopperTrak.

But business dropped 1.8 percent to $11.2 billion on Black Friday, though it still was the biggest shopping day last year. That day accounted for about 4.3 percent of holiday sales last year.

“Customers clearly showed that they wanted to be out shopping much earlier on Thanksgiving,” Amy von Walter, a spokeswoman for Best Buy, which moved up its opening this year to 6 p.m. on Thanksgiving from midnight on Black Friday in 2012. “Our plan this holiday is a direct result of that feedback.”

To be sure, the issue is divisive among shoppers. Some believe that the holiday should remain sacred and that store employees should not have to work. Some even have threatened on retailers’ Facebook pages that they will boycott stores that open on Thanksgiving.

Jennifer Gillis, 49, refused to shop during the holidays at Sears and Kmart last year because she believes Thanksgiving should not be commercialized. This year, she’s adding Macy’s to the list.

“I think it’s turning into a day of greed — for shoppers and stores,” Gillis, who lives in Hawaii, says.

Given the controversy, opening on Thanksgiving can be a difficult decision for retailers to make.

For instance, last year, Macy’s and J.C. Penney didn’t open on Thanksgiving evening as competitors did. Both chains say they wanted to honor their workers’ time with their families. But this year, they changed their tune.

Tony Bartlett, executive vice president of Penney’s stores, says the company decided to open at 8 p.m. on Thanksgiving this year because of customer feedback. He also says Penney store employees wanted to open on Thanksgiving so they could get the chance to better compete with rivals.

“Obviously, we were one of the last to open,” last year, says Bartlett, referring to the chain’s 6 a.m. opening in 2012. But he says this year, “We’re all in.”

Not every store is opening on turkey day, though. A couple of retailers even put out statements specifically noting that they won’t be opening on Thanksgiving so that their employees won’t have to work.

“We believe it is important for our team members to be able to spend this time with their loved ones,” Travis Smith, CEO and president of Jo Ann Fabric and Craft Stores, says in a statement. The retailer plans to open at 6 a.m. on Black Friday.

B.J.’s Wholesale Club also says it will not open on Thanksgiving. “Once again, BJ’s is bucking the trend of putting sales on Thanksgiving above family time,” BJ’s says in a statement in which it announced that it would open stores at 7 a.m. on Black Friday.